Basic demographic information for the participants in each analysis. For age and age at menopause, the mean and standard deviation, in parentheses, are shown. The number of participants who used HT as well as the proportion of the total sample that they represent is also reported. For SES, the values represent the number of participants in each of the following income categories, in pounds sterling: less than 18,000/18,000-30,999/31,000-51,999/52,000-100,000/greater than 100,000. Over 90% of the sample identifies as ethnically white.